shirok/gumowski-mira.html

## gumowski-mira.html
<html>
  <body>
    <form action="#">
      α: <input type="text" id="α" value="0.008"/>
      σ: <input type="text" id="σ" value="0.05"/>
      μ: <input type="text" id="μ" value="-0.496"/>
      <button type="button" onclick="plot()">redraw</button>
    </form>
    <canvas id="canvas" width="1000" height="1000"></canvas>

    <script><!--
      const canvas = document.getElementById('canvas');
      const ctx = canvas.getContext('2d');
      const N0 = 2000, Nmax = 100000;
      const x0 = 10.0, y0 = 10.0;

      function dot(x, y) {
        ctx.fillRect((x+20)*canvas.width/40, (20-y)*canvas.height/40, 1, 1);
      }

      function gm(α, σ, μ) {
        function step(x, y) {
          var x1 = y + α*y*(1-σ*y*y) + μ*x + 2*(1-μ)*x*x/(1+x*x);
          var y1 = -x + μ*x1 + 2*(1-μ)*x1*x1/(1+x1*x1);
          return [x1, y1];
        }

        var x = x0, y = y0, i = 0;
        for (; i < N0; i++) {
          [x, y] = step(x, y);
        }
        for (; i < Nmax; i++) {
          [x, y] = step(x, y);
          dot(x, y);
        }
      }

      function plot() {
        ctx.clearRect(0, 0, canvas.width, canvas.height);
        gm(parseFloat(document.getElementById('α').value),
           parseFloat(document.getElementById('σ').value),
           parseFloat(document.getElementById('μ').value));
      }

      plot();
    -->
    </script>

  </body>
</html>
	<html>
	<body>
	<form action="#">
	α: <input type="text" id="α" value="0.008"/>
	σ: <input type="text" id="σ" value="0.05"/>
	μ: <input type="text" id="μ" value="-0.496"/>
	<button type="button" onclick="plot()">redraw</button>
	</form>
	<canvas id="canvas" width="1000" height="1000"></canvas>

	<script><!--
	const canvas = document.getElementById('canvas');
	const ctx = canvas.getContext('2d');
	const N0 = 2000, Nmax = 100000;
	const x0 = 10.0, y0 = 10.0;

	function dot(x, y) {
	ctx.fillRect((x+20)canvas.width/40, (20-y)canvas.height/40, 1, 1);
	}

	function gm(α, σ, μ) {
	function step(x, y) {
	var x1 = y + αy(1-σyy) + μx + 2(1-μ)xx/(1+x*x);
	var y1 = -x + μx1 + 2(1-μ)x1x1/(1+x1*x1);
	return [x1, y1];
	}

	var x = x0, y = y0, i = 0;
	for (; i < N0; i++) {
	[x, y] = step(x, y);
	}
	for (; i < Nmax; i++) {
	[x, y] = step(x, y);
	dot(x, y);
	}
	}

	function plot() {
	ctx.clearRect(0, 0, canvas.width, canvas.height);
	gm(parseFloat(document.getElementById('α').value),
	parseFloat(document.getElementById('σ').value),
	parseFloat(document.getElementById('μ').value));
	}

	plot();
	-->
	</script>

	</body>
	</html>